A gas turbine engine typically includes a compressor section, a combustor section and a turbine section. Air entering the compressor section is compressed and delivered into the combustion section where it is mixed with fuel and ignited to generate a high temperature exhaust gas flow. The exhaust gas flow is then turned tangentially, and accelerated by turbine inlet guide vanes such that the high-speed exhaust gas flow expands through the turbine section to drive the compressor.
Premixing fuel and air prior to combustion in the combustion chamber has become the most widely employed method for achieving low oxides of nitrogen (NOx) emissions from a gas turbine. However, in many alternate fuels, particularly hydrogen-containing fuels, premixing the fuel and air presents challenges to prevent flashback, autoignition, and other premixer burning. Premixing may also increase the likelihood of large pressure pulsations driven by combustion dynamics. These challenges are heightened if the fuel composition varies from the design values used in the development of the combustor. Accordingly, it is desirable to design and develop devices that provide a thorough mixing of fuel and air for the combustion process that are also fuel-flexible to the extent that variations in fuel composition and hydrogen content are tolerated with no adverse effects.